Classifications

• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10G—CRACKING HYDROCARBON OILS; PRODUCTION OF LIQUID HYDROCARBON MIXTURES, e.g. BY DESTRUCTIVE HYDROGENATION, OLIGOMERISATION, POLYMERISATION; RECOVERY OF HYDROCARBON OILS FROM OIL-SHALE, OIL-SAND, OR GASES; REFINING MIXTURES MAINLY CONSISTING OF HYDROCARBONS; REFORMING OF NAPHTHA; MINERAL WAXES
  • C10G19/00—Refining hydrocarbon oils in the absence of hydrogen, by alkaline treatment
• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10G—CRACKING HYDROCARBON OILS; PRODUCTION OF LIQUID HYDROCARBON MIXTURES, e.g. BY DESTRUCTIVE HYDROGENATION, OLIGOMERISATION, POLYMERISATION; RECOVERY OF HYDROCARBON OILS FROM OIL-SHALE, OIL-SAND, OR GASES; REFINING MIXTURES MAINLY CONSISTING OF HYDROCARBONS; REFORMING OF NAPHTHA; MINERAL WAXES
  • C10G17/00—Refining of hydrocarbon oils in the absence of hydrogen, with acids, acid-forming compounds or acid-containing liquids, e.g. acid sludge
• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10G—CRACKING HYDROCARBON OILS; PRODUCTION OF LIQUID HYDROCARBON MIXTURES, e.g. BY DESTRUCTIVE HYDROGENATION, OLIGOMERISATION, POLYMERISATION; RECOVERY OF HYDROCARBON OILS FROM OIL-SHALE, OIL-SAND, OR GASES; REFINING MIXTURES MAINLY CONSISTING OF HYDROCARBONS; REFORMING OF NAPHTHA; MINERAL WAXES
  • C10G17/00—Refining of hydrocarbon oils in the absence of hydrogen, with acids, acid-forming compounds or acid-containing liquids, e.g. acid sludge
  • C10G17/02—Refining of hydrocarbon oils in the absence of hydrogen, with acids, acid-forming compounds or acid-containing liquids, e.g. acid sludge with acids or acid-containing liquids, e.g. acid sludge
• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10G—CRACKING HYDROCARBON OILS; PRODUCTION OF LIQUID HYDROCARBON MIXTURES, e.g. BY DESTRUCTIVE HYDROGENATION, OLIGOMERISATION, POLYMERISATION; RECOVERY OF HYDROCARBON OILS FROM OIL-SHALE, OIL-SAND, OR GASES; REFINING MIXTURES MAINLY CONSISTING OF HYDROCARBONS; REFORMING OF NAPHTHA; MINERAL WAXES
  • C10G29/00—Refining of hydrocarbon oils, in the absence of hydrogen, with other chemicals
  • C10G29/06—Metal salts, or metal salts deposited on a carrier
• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10G—CRACKING HYDROCARBON OILS; PRODUCTION OF LIQUID HYDROCARBON MIXTURES, e.g. BY DESTRUCTIVE HYDROGENATION, OLIGOMERISATION, POLYMERISATION; RECOVERY OF HYDROCARBON OILS FROM OIL-SHALE, OIL-SAND, OR GASES; REFINING MIXTURES MAINLY CONSISTING OF HYDROCARBONS; REFORMING OF NAPHTHA; MINERAL WAXES
  • C10G29/00—Refining of hydrocarbon oils, in the absence of hydrogen, with other chemicals
  • C10G29/06—Metal salts, or metal salts deposited on a carrier
  • C10G29/10—Sulfides

Definitions

• This invention relates to reducing hydrolysis of hydrocarbon streams such as crude oil that are subjected to processing at elevated temperatures and, more particularly, to reducing hydrolysis and the subsequent production of hydrochloric acid by the addition of hydrolysis inhibitors to such streams.
• a typical refinery includes a tank farm or storage area where feed stocks, e.g., crude oil, shale oil, coal oil and certain intermediate hydrocarbon streams from the refining processes are stored for optimum utilization in the refinery. It is not uncommon for these feedstocks to contain chloride salts, primarily metal chloride salts and, more particularly, chlorides of alkali and alkaline earth metals in amounts ranging from 1 to 2000 ppm. It is known that hydrocarbon streams containing these chloride contaminants, at elevated temperatures and in the presence of water, will hydrolyze to form hydrochloric acid, which, as well known to those skilled in the art, can cause severe corrosion problems to processing equipment.
• chloride salts primarily metal chloride salts and, more particularly, chlorides of alkali and alkaline earth metals
• the crude is generally first treated in a desalter.
• the purpose of the desalter is to remove as much of the salts and other water soluble contaminants as possible prior to introducing the hydrocarbon stream, e.g., the crude oil, to the downstream heat exchangers, furnaces, distillation columns, crackers and the associated processing equipment such as pumps, valves, piping and other equipment commonly used in refineries and other petrochemical facilities.
• the desalter which generally operated at a temperature of 200° to 250°F, it passes through a second heating zone operated at a temperature of about 250° to 600°F.
• the heated stream then passes to a furnace where it is heated to a temperature of 600° to 700°F.
• the stream is next introduced into an atmospheric distillation column together with steam to make a rough fractionation into generally four cuts: an overhead stream containing light hydrocarbon, e.g., C, to C g hydrocarbon, a first intermediate fraction comprising kerosene, jet and diesel fuel, a second intermediate fraction containing gas oil, and a bottoms fraction containing the heaviest components present in the feedstock.
• light hydrocarbon e.g., C, to C g hydrocarbon
• a first intermediate fraction comprising kerosene, jet and diesel fuel
• a second intermediate fraction containing gas oil e.g., kerosene, jet and diesel fuel
• a bottoms fraction containing the heaviest components present in the feedstock e.g., kerosene, jet and diesel fuel
• a bottoms fraction containing the heaviest components present in the feedstock e.g., it is
• a method for reducing hydrolysis in a hydrocarbon stream wherein a hydrocarbon stream containing a chloride compound which undergoes hydrolysis at elevated temperatures and in the presence of water to form hydrochloric acid is treated with an effective amount of a treating agent comprising at least one overbase complex of a metal salt and an organic acid complexing agent.
• the treating agent is introduced into the hydrocarbon stream when the stream is at a temperature below which any substantial hydrolysis of the chloride containing compound occurs.
• Fig. 1 is a graph showing the hydrolysis of various metal chlorides in mineral oil as a function of temperature.
• Fig. 2 is a graph showing the effect of various contaminants on the hydrolysis of calcium chloride in mineral oil as a function of temperature.
• Fig. 3 is a graph showing the hydrolysis of sodium chloride in mineral oil in the presence of naphthenic acid as a function of temperature.
• Fig. 4 is a graph showing the inhibition of hydrolysis of calcium chloride using the method of the present invention
• Fig. 5 is a graph showing the inhibition of mixed chloride salts in mineral oil using the method of the present invention.
• the method of the present invention while finding particular application to crude feedstocks in refinery operations, can be used in any hydrocarbon stream and any process wherein the hydrocarbon stream contains hydrolyzeable chloride compounds, which, at elevated temperatures and in the presence of water can form hydrochloric acid.
• suitable hydrocarbon streams include crude oil, shale oil, coal oil, as well as various hydrocarbon streams that are produced in refinery operation and that are generally used as intermediates to produce other, more desirable products.
• the chloride containing compounds can be any compound, generally inorganic in nature, that will hydrolyze at elevated temperatures and in the presence of water to form hydrochloric acid.
• the chloride containing compounds are metal salts and, more particularly, salts of the alkali and alkaline earth metals, such as sodium chloride, calcium chloride, magnesium chloride, etc.
• a treating agent comprised of an overbase complex of a metal salt and an organic acid complexing agent, described hereafter, is introduced into the chloride contaminated hydrocarbon streams prior to the stream being raised to a range at which any significant hydrolysis occurs, hydrolysis of the resulting chloride is greatly diminished, often to a point where minimal corrosion occurs.
• the hydrolysis of the chloride containing compounds to form hydrochloric acid occurs generally over a temperature range depending upon the specific conditions, the particular chloride(s) and other such variables.
• the treating agent of the present invention is preferably introduced into the feed stream prior to the time the stream enters the second heating section, i.e., the heating section following the desalter and upstream of the furnace.
• the treating agent can be introduced well downstream of the second heating section and, indeed, can be introduced with the crude that may be an ambient or below ambient temperatures, i.e., prior to the first preheating section.
• the treating agent can be introduced into the heating section between the desalter and the furnace, although it is preferable that it be introduced prior to the stream entering the second heating section.
• Naphthenic acid corrosion generally occurs in the temperature range of from 400° to 600°F, i.e., at a temperature significantly higher than that at which hydrolysis of the chloride contaminant occurs.
• the treating agent is introduced into the stream at some point prior to the stream entering the second heating section, i.e., the heating section between the desalter and the furnace, it would be effective at reducing naphthenic acid corrosion, as well as hydrolysis of the chloride contaminants.
• naphthenic acid greatly increases the hydrolysis of chloride salts such as sodium chloride.
• the treating agent used in this invention comprises at least one overbase complex of a salt and an organic acid complexing agent.
• overbases are not well-understood.
• they comprise dispersions of salts formed by contacting an acidic material with an excess of a basically reacting metal compound; e.g., a metal hydroxide or oxide.
• a basically reacting metal compound e.g., a metal hydroxide or oxide.
• the treating agent is an overbase complex of an oxide or carbonate of Mg, Ca, Ba, Sr or Mn and the Mg, Ca, Ba, Sr or Mn salt of an organic acid "complexing agent".
• Mg, Ca, Ba, Sr or Mn Mg, Ca, Ba, Sr or Mn salt of an organic acid "complexing agent".
• overbases include the aluminum species.
• the treating agent contains a stoichiometric excess of basic metal compound, relative to the number of equivalents of acid complexing agent which is reacted with a basic metal compound to afford the complex, relative to the normal stoichiometry of the particular metal base and acid.
• a "neutral" or “normal” metal salt of an acid is characterized by an equivalent ratio of base or "metal” to acid of 1 : 1
• an overbased salt is characterized by a higher ratio; e.g., 1.1:1, 2: 1, 5: 1, 10: 1, 15:1, 20: 1, 30: 1 and the like.
• metal ratio is used to designate the ratio of (a) equivalents of metal or base to acid in an overbased salt to (b) the number of equivalents expected to be present in a normal salt, based on the usual stoichiometry of the metal or metals involved and the acid of acids present.
• an oil dispersion of an overbased magnesium salt containing two equivalents of acid and twenty equivalents of magnesium would have a metal ratio of 10; i.e., 20/(1+1).
• magnesium for example, is regarded as having two equivalents of base per atomic weight; magnesium oxide (MgO) and magnesium hydroxide (Mg(COH 2 ), two equivalents per mole.
• Monobasic organic acids are regarded as having one equivalent of acid per acidic hydrogen or acid group.
• a monocarboxylic acid or monosulfonic acid or their equivalent derivatives such as esters and ammonium and metal salts, have one equivalent per mole of acid, ester or salt; a disulfonic acid or dicarboxylic acid, or equivalent derivative, has two equivalents per mole.
• the basically reacting metal compounds such as the oxides and carbonates of calcium, barium and magnesium have two equivalents per mole; i.e., two equivalents per atomic weight of metal.
• the treating agents used in the method of the present invention are overbase complexes of metal oxides and/or carbonates and a metal salt of at least one complexing agent.
• the oxides or carbonates may also be a combination of the metal species, such as a 1 : 1 by weight mixture.
• the salt may be a combination of metal salts, such as a 1 : 1 by weight mixture.
• the magnesium, calcium or aluminum species are highly preferred.
• carboxylate refers to the reaction product of a metal base and an organic carboxylic acid having the general formula R--COOH, where R is a hydrocarbon radical
• non-carboxylate refers to the reaction product of a metal base and an organic acid other than an organic carboxylic acid; e.g., “non-carboxylic” acids such as organic sulfiir acids and organic phosphorus acids, which latter materials have substantially greater dispersant capabilities than do the carboxylates, the carboxylates, however, having stabilizing capabilities.
• the role of the complexing agent in the preparation and use of the treating agents in the invention is not clear. As stated above, some may function as stabilizers while others may function as dispersants. Certainly, some may have both functions or another, unknown, function. It appears, however, that, during the preparation of the complex, the presence of at least one complexing agent is essential to provide the treating agent used in the method of the invention. It also appears that the preferred treating agents are characterized by the presence of a non-carboxylate salt; e.g., a sulfonate.
• the treating agents used in the present invention may be prepared in any manner known to the prior art for preparing overbased salts, providing that the magnesium oxide/magnesium carboxylated overbase complex resulting therefrom is in the form of finely divided, preferably submicron, particles which form a stable dispersion in oil.
• the method for-preparing the magnesium oxide/magnesium carbox-ylated-overbase eomplex- is to form a mixture of a base of the desired metal; e.g., Mg(OH 2 ), a complexing agent; e.g., fatty acid such as a tall oil fatty acid, which is present in a quantity much less than that required to stoichiometrically react with the hydroxide, and a non-volatile diluent.
• the mixture is heated to a temperature of about 250° to 350°C, whereby there is afforded the overbase complex of the metal oxide and metal salt of the fatty acid as set forth in U.S. Pat. No. 4,163,728 (the '728 patent).
• the metal carbonate/complexing agent overbase complex e.g., magnesium carbonate/magnesium sulfonate
• the above-described method of preparing the overbased magnesium oxide/magnesium carboxylate treating agent used in the present invention is particularly set forth in the '728 patent, which is incorporated herein by reference in its entirety and made a part hereof, wherein, for example, a mixture of Mg(OH) 2 and a carboxylic acid complexing agent is heated at a temperature of about 280° to 330°C. in a suitable non- volatile diluent.
• Complexing agents are carboxylic acids, phenols, organic phosphorus acids and organic sulfur acids. Included are those acids which are presently used in preparing overbased materials; e.g., those described in U.S. Pat. Nos. 3,312,618; 2,695,910 and 2,616,904, and constitute an art-recognized class of acids.
• the carboxylic acids, phenols, organic phosphorus acids and organic sulfur acids which are oil-soluble per se, particularly the oil-soluble sulfonic acids, are especially useful.
• Oil-soluble derivatives of these organic acidic substances can be utilized in lieu of or in combination with the free acids.
• organic acidic substances such as their metal salts, ammonium salts and esters (particularly esters with lower aliphatic alcohols having up to six carbon atoms, such as the lower alkanols)
• esters particularly esters with lower aliphatic alcohols having up to six carbon atoms, such as the lower alkanols
• Suitable carboxylic acid complexing agents which maybe used to make the treating agent include aliphatic, cycloaliphatic and aromatic mono and polybasic carboxylic acids such as naphthenic acids, alkyl- or alkenyl-substituted cyclopentanoic acids, alkyl- or alkenyl-substituted cyclohexanoic acids and alkyl- or alkenyl-substituted aromatic Garboxylic acids.
• the aliphatic acids generally are long chain acids and contain at least eight carbon atoms and preferably at least twelve carbon atoms.
• the cycloaliphatic and aliphatic carboxylic acids can be saturated or unsaturated.
• Specific examples include 2-ethylhexanoic acid, alphalinolenic acid, propylene-tetramer-substitutedmaleic acid, behenic acid, isostearic acid, pelargonic acid, capric acid, palmitoleic acid, linoleic acid, lauric acid, oleic acid, ricinoleic acid, undecyclic acid, dioctylcyclopentane carboxylic acid, myristic acid, dilauryldecahydronaphthalene carboxylic acid, stearyl-octahydroindene carboxylic acid, palmitic acid, commercially available mixtures of two or more carboxylic acids such as tall oil fatty acids, rosin acids and the like.
• saturated aliphatic monocarboxylic acids e.g., formic, acetic, propionic, butyric, valeric, caproic, heptanoic, caprylic, pelargonic, capric, undecyclic, lauric, tridecylic, myristic, isoacetic, palmitic, margaric and stearic; alicyclic unsaturated monocarboxylic acids; e.g.
• saturated aliphatic dicarboxylic acids e.g., oxalic, malonic, succinic, glutaric, adipic, pimelic, suberic, azelaic and sebacic
• alicyclic saturated dicarboxylic acids e.g., cyclohexane dicarboxylic acid
• unsaturated aliphatic monocarboxylic acids e.g., acrylic, crotonic, decenoic, undecenoic, tridecenoic, pentadecenoic, oleic, linoleic and linolenic
• unsaturated dicarboxylic acids e.g., fumaric and maleic.
• Aromatic acids which are used in the preparation of the treating agent are represented by the general formula:
• R is a hydrocarbon or essentially hydrocarbon radical containing at least four aliphatic carbon atoms
• R' is hydrogen or C(X)XH
• n is an integer of from one to four
• Ar is a polyvalent aromatic hydrocarbon radical having a total of up to fourteen carbon atoms in the aromatic nucleus
• each X is independently a divalent sulfur or oxygen group
• p is zero or an integer of from one to six, with the proviso that R and n are such that there is an average of at least eight aliphatic carbon atoms provided by the R substituents for each acid molecule represented.
• aromatic radicals represented by the variable Ar are the polyvalent aromatic radicals derived from benzene, naphthalene, anthracene, phenanthrene, indene, fluorene, biphenyl and the like.
• the radical represented by Ar will be a polyvalent radical derived from benzene or naphthalene such as phenylenes and naphthalene; e.g., methylphenylenes, mercaptophenylenes, N,N-diethylaminophenylenes, chlorophenylenes, dipropoxynaphthylenes, triethylnaphthylenes, and similar tri-, terra- and pentavalent radicals thereof.
• the R variables are usually hydrocarbon groups, preferably aliphatic hydrocarbon groups such as alkyl or alkenyl radicals.
• R groups include butyl, isobutyl, octyl, nonyl, dodecyl, docosyl, tetracontyl, t- chlorohexyl, 4-ethoxypentyl, 4-hexenyl, 3-cyclohexy ctyI, 4-(p-chlorophenyl)-octyl, 2,3,5,- trimethyl, 4-ethyl-5-methyloctyl and substituents derived from polymerized olefins such as polychloroprenes, polyethylenes, propypropylenes, polyisobutylenes, ethylenepropylene copolymers, chlorinated olef ⁇ n polymers, oxidized ethylene-propylene copolymers and the like.
• polymerized olefins such as polychloroprenes, polyethylenes, propypropylenes, polyisobutylenes, ethylenepropylene copolymers, chlorinated
• variable Ar may contain non-hydrocarbon substituents, for example, such diverse substituents as lower alkoxy, lower alkyl mercapto, nitro, halo, alkyl or alkenyl groups of less than four carbon atoms, hydroxy, mercapto and the like.
• aromatic carboxylic acids are those of the formula:
• a is an integer of from 1 to 3
• b is 1 or 2
• c is zero, 1 or 2 and preferably 1, with the proviso that ' and a are such that the acid molecules contain at least an average of about twelve aliphatic carbon atoms in the aliphatic hydrocarbon substituents per acid molecule.
• Phenols which are used include 3,5,5-trimethyl-n-hexyl phenol, -decyl phenols, cetyl phenols, nonyl phenols, alkylphenol phenols, resorcinol, octyl catechol, triisobutyl pyrogallol, alkyl alpha naphthol and the like.
• non-carboxylic acids which may be used in preparing the processing aids are the organic sulfur acids; e.g., oil-soluble sulfonic acids, including the synthetic oil-soluble sulfonic acids.
• oil-soluble sulfonic acids are represented by the general formula:
• T is a cyclic nucleus of the mono- or polynuclear type including benzenoid, cycloaliphatic or heterocyclic nuclei such as a benzene, naphthalene, anthracene, 1 ,2,3,4-tetrahydronaphthalene, thianthrene, cyclopentene, pyridine or biphenyl and the like. Ordinarily, however, T will represent an aromatic hydrocarbon nucleus, especially a benzene or naphthalene nucleus.
• variable R in the radical R ⁇ can be, for example, an aliphatic group such as alkyl, alkenyl, alkoxy alkoxyalkyl, carboalkoxyalkyl, an aralkyl group or other hydrocarbon or essentially hydrocarbon groups, while x is at least 1 with the proviso that the variables represented by the group R.. are such that the acids are oil-soluble.
• the groups represented by R should contain at least about eight aliphatic carbon atoms and preferably at least about twelve aliphatic carbon atoms. Generally x -will-be aninteger of 1-3.
• the variables r and y in Formulae I and II have an average value of one to about four per molecule.
• variable R' in Formula II is an aliphatic or aliphatic-substituted cycloaliphatic hydrocarbon or essentially hydrocarbon radical.
• R* is an aliphatic radical, it should contain at least about 8 to about 20 carbon atoms and where R' is an aliphatic-substituted cycloaliphatic group, the aliphatic substituents should contain about 4 to 16 carbon atoms.
• R are alkyl, alkenyl and alkoxyalkyl radicals and aliphatic-substituted cycloaliphatic radicals wherein the aliphatic substituents are alkoxy, alkoxyalkyl, carboalkoxyalkyl, etc.
• the cycloaliphatic radical will be a cycloalkane nucleus or a cycloalkene nucleus such as cyclopentane, cyclohexane, cyclohexene, cyclopentene and the like.
• R' are cetyl-cyclohexyl, laurylcyclohexyl, cetyloxyethyl and octadecenyl radicals, and the radicals derived from petroleum, saturated and unsaturated paraffin wax, and polyolefins, including polymerized mono- and diolefins containing from about I to 8 carbon atoms per olefin monomer unit.
• the groups T, R and R in Formulae I and II can also contain other substituents such as hydroxy, mercapto, halogen, nitro, amino, nitroso, carboxy, lower carbalkoxy, etc., as long as the essentially hydrocarbon character of the groups not destroyed.
• the sulfonic acids which are preferred for use herein include alkyl sulfonic acids, alkaryl sulfonic acids, aralkyl sulfonic acids, dialkyl sulfonic acids, dialkylaryl sulfonic acids, aryl sulfonic acids; e.g., ethylsulfonic acid, benzenesulfonic acid, dodecylbenzenesulfonic acid and more complex sulfonic acid mixtures such as mahogany sulfonic acids and petroleum sulfonic acids.
• illustrative examples of the sulfonic acids are mahogany sulfonic acids, petrolatum sulfonic acids, mono- and polywax-substituted naphthalene sulfonic acids, cetylchlorobenzenesulfonic acids, cetylphenol sulfonic acids, cetylphenol disulfide sulfonic acids, cetoxycaprylbenzene sulfonic acids, dicetyl thianthrene sulfonic acids, di-lauryl betanaphthol sulfonic acids, dicapryl nitronaphthylene sulfonic acids, paraffin wax sulfonic acids, unsaturated paraffin wax sulfonic acids, hydroxy-substituted paraffin wax sulfonic acidSj-tetraisobutylene sulfonic acids, tetraamylene sulfonic acids, chlororsubstituted paraffin wax s
• Organic phosphorus acids used herein are characterized by at least one oil- solubilizing group attached directly to phosphorus via a carbon atom; e.g., oil-soluble phosphoric, phosphinic and phosphonic acids including the oil-soluble thiophosphoric, thiophosphinic and thiophosphonic acids.
• Preferred phosphorus acids are the alkyl- and dialkyl phosphoric and phosphonic acids and those prepared by reacting olefins with phosphorus sulfides; e.g., phosphorus pentasulfide. Steam-treated reaction products of phosphorus pentasulfide and polyolefins, such as polyisobutylene and polypropylene, are also useful.
• Overbase complex types which are the preferred treating agents used in the invention are the following:
• carboxylate and “non-carboxylate” refers, as stated supra, to the partial reaction product of a base of the desired metal and a carboxylic or non-carboxylic acid complexing agent which affords a complex believed to be a dispersion of finely divided metal oxide (or carbonate) associated with the metal carboxylate or metal non-carboxylate.
• more than one oxide or carbonate may be associated with a complexing agent to afford complexes, for example, of the type MgO/MgCO 3 /Mg-non-carboxylate, and more than one complexing agent may be combined with an oxide or carbonate to afford complexes, for example, of the type MgO Mg carboxylate Mg-non-carboxylate and MgCO 3 /carboxylate/Mg-non-carboxylate.
• Corresponding aluminum versions are believed to be possible alternatives.
• mixed overbase complexes are included; e.g., MgO/Mg carboxylate with MgO/Mg non-carboxylate, MgCO 3 /carboxylate with MgCO 3 non-carboxylate, MgO/Mg carboxylate with MgCO 3 /non-carboxylate, etc.
• corresponding aluminum versions are believed to be possibilities as well.
• MgCO 3 /Mg sulfonate MgCO 3 /Mg carboxylate MgO/Mg sulfonate+MgCO 3 Mg carboxylate MgO/MgCO 3 Mg carboxylate MgO/MgCO 3 /Mg sulfonate
• MgO/Mg fatty acid carboxylate especially "tall oil” fatty acid carboxylates
• MgCO 3 Mg fatty acid carboxylate MgCO 3 /Mg benzenesulfonate or dodecylbenzenesulfonate MgO/Mg fatty acid carboxylate+MgO/Mg benzenesulfonate or dodecylbenzene sulfonate
• the mixed overbase complexes e.g., MgO/Mg fatty acid carboxylate+MgCO 3 /Mg benzenesulfonate, are in a weight ratio to each other of from about 0.25/10 to about 10/0.25.
• the reaction of metal base and acid affords a product which undergoes decomposition to afford minute particles of metal oxide or carbonate in associate with the metal salt of the acid.
• the minute particles immediately become suspended and stabilized by the metal salt of the acid.
• the particles of metal oxide or metal carbonate are of a size no greater than about 2 microns in diameter, for example, not greater than about 1 micron but, preferably no greater than about 0.1 micron and, especially, should be less than 0.1 micron in diameter.
• the preparation of a stable, fluid magnesium dispersion comprises decomposing a magnesium carboxylate to MgO in a non-volatile process fluid capable of being heated to the decomposition temperature of the magnesium carboxylate also containing a dispersant capable of retaining the magnesium oxide formed by the decomposition in stable suspension at a temperature greater than about 230°C, the process containing less than a stoichiometric amount of carboxylate, based on Mg(OH) 2 or equivalent.
• the magnesium oxide dispersion can be further reacted, after decomposition, with CO to form MgCO 3 dispersions, with water to form Mg(OH) 2 dispersions, etc.
• the overbases by nature, therefore, are colloidal dispersions that may be added as "liquids" to the hydrocarbon streams as discussed above. Upon addition to the hydrocarbon streams, the overbases have been found to disperse easily and to tend to remain well- dispersed. In this sense, the overbases are "oil-soluble” in that they form well-dispersed colloidal suspensions in the hydrocarbon- streams such as crude oil.
• the amount of treating agent, which is used will vary, depending on the environment of the area, the type of chloride salt and its concentration in the hydrocarbon stream being treated. Generally, at least about 0.5 ppm by weight of available metal per I ppm by weight chloride salt is desired. However, at least 1 ppm by weight available metal per 1 ppm by weight chloride salt is preferred due to possible inefficiencies.
• an amount of treating agent is used which is effective for reducing hydrolysis. This is referred to herein as an "effective amount". Accordingly, there may be used an amount of from about 5 ppm to about 1,000 ppm or more based on the chloride salt concentration and type contained in the hydrocarbon stream, depending on specific circumstances. Ordinarily, from about 25 ppm to about 500 ppm are effective, especially from about 50 to about 300 ppm.
• the concentrations of treating agent discussed above are generally maintained on a continuous basis.
• the treating agent is added continuously in an amount necessary to effect a constant concentration of, for example, from about 25 to about 500 ppm, especially from about 50 to about 300 ppm.
• the treating agent may be added in a single dose or on a semi-continuous basis.
• the treating agent may be added as a liquid or, in the case of addition to a gas stream, as a spray.
• the method of the present invention was studied in a laboratory using a prepared mineral oil and a synthetic crude oil comprised of mineral oil with various contaminants normally found in crude oil.
• a steam distillation apparatus was assembled for conducting steam distillation of the synthetic crude oil in the range of 300°F to 650°F at atmospheric pressure.
• the synthetic crude oil in addition to mineral oil and chloride salts contained iron oxide, silica, iron sulfide, drilling mud and naphthenic acids.
• the contaminants were selected to represent actual field conditions. In this regard, it is known that iron oxide and sulfide are formed when corrosion of upstream equipment occurs. Silicon is commonly produced with crude oil as a result of fractured rock formation. Drilling mud is usually present in crude oil from new production formations or workover wells. Naphthenic acids are found in varyirig ⁇ amounts in almost all c ⁇ de oils.
• the metal salts employed were sodium chloride, magnesium chloride and calcium chloride, and were added to the mineral oil as a fine powder and mixed for five minutes in a high speed blender to produce a stable suspension.
• the hexahydrate form of magnesium chloride and the dihydrate form of calcium chloride were selected since these forms would likely be present in crude oils that had been previously exposed to water.
• Anhydrous sodium chloride was used because no hydrates of sodium chloride are likely to exist in crude oil.
• the oil salt suspension was then heated along with the contaminants to be tested to the test temperature, at which time steam purging was starting at lg/min and continued until lOg of condensate was recovered.
• the condensate was then analyzed for chloride using mercury nitrate titration and ion chromatography. In all cases, the results are reported as percent of the initial chloride, which was added to the synthetic crude or mineral oil as sodium, calcium or magnesium salt.
• Steam condensate samples were collected at 50°F intervals between 300°F and 650°F. The results are shown in the figures, graphically, as plots of percent of total chloride added per lOg steam condensate (y axis vs. temperature (x axis).
• the hydrolysis of the three metal chlorides in mineral oil is shown in Fig. 1.
• the samples contained 210 ppm Cl as Mg Cl 2 .6 H 2 0, 244 ppm Cl as CaCl 2 .2 H 2 0 and 1450 ppm Cl as NaCl.
• the hydrolysis rates for sodium and calcium chlorides are observed to be very low while the hydrolysis rate for magnesium chloride hexahydrate goes through a maximum at between 400°F and 500°F, and is likely to be caused as a result of magnesium hydroxychloride, a stable form of chloride, which, on formation tends to slow down the hydrolysis rate.
• the overall efficiency of the hydrolysis of metal chloride to hydrochloric acid was determined with respect to the contaminants, which may act either as catalyst or inhibitors for the reaction.
• the most important contaminant is naphthenic acid, which caused a tenfold increase in the hydrolysis of sodium and calcium chloride.
• the effect of all other contaminants is n , as shown in Fig. 2.
• other contaminants were 0.7 wt. % Fe O, 1.0 wt. % Fe S, 0.6 wt. %, S10 2 and 2.0 wt. % drilling mud.
• Fig. 3 demonstrates the power of naphthenic acid to accelerate the hydrolysis of sodium chloride, a normally stable salt.
• Example 1 This example demonstrates the effectiveness of using the method of the present invention to reduce the hydrolysis of calcium chloride in a hydrocarbon base such as diluted bitumen.
• a hydrocarbon base such as diluted bitumen.
• diluted bitumen containing 0.291 grams of calcium chloride, but no treating agent (inhibitor) was subjected to steam distillation as per the method described above.
• the same diluted bitumen blend, together with 4g of a treating agent inhibitor which was a calcium overbase having a total base number of 400 was also subjected to steam distillation.
• the results are shown graphically in Fig. 4. As can be seen, with no inhibitor significant hydrolysis of the calcium chloride occurred at a temperature of 450°. This is to be contrasted with the sample that contained the treating agent in which no significant hydrolysis of the calcium chloride was observed.
• Example 2 This example demonstrates the ability of the method of the present invention to prevent the hydrolysis of mixed chloride salts in a synthetic crude.
• the synthetic crude was as described above, e.g., mineral oil containing iron oxide, iron sulfide, silica and drilling mud in the amounts shown in Fig. 2.
• the total volume of mineral oil was 800 ml. which contained 3.5 g. sodium chloride, 1.0g. calcium chloride, 0.5g. magnesium chloride, arid 8g. of naphthenic acid.
• the treating agent employed was a magnesium overbase compound having a total base number of 600.
• a sample of the synthetic crude with the chloride salts and no treating agent was subj ected to steam stripping as described above.
• a second sample was also subjected to steam stripping, except in this case, there were three parts of inhibitor for five parts of combined chloride salts.
• a third experiment was conducted in which there were six parts of inhibitor for five parts of combined salts. The results are shown in Fig. 5.
• hydrolysis of the chlorides in the synthetic crude commenced at a roughly 250-300°F. With three parts of treating agent per five parts of salts present, hydrolysis was greatly reduced showing a peak at about 400°F. With six parts of treating agent per five parts of salts, hydrolysis was reduced to a point where minimum make of hydrochloric acid occurred.

Landscapes

• Chemical & Material Sciences (AREA)
• Oil, Petroleum & Natural Gas (AREA)
• Engineering & Computer Science (AREA)
• Chemical Kinetics & Catalysis (AREA)
• General Chemical & Material Sciences (AREA)
• Organic Chemistry (AREA)
• Production Of Liquid Hydrocarbon Mixture For Refining Petroleum (AREA)
• Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)

Applications Claiming Priority (5)

Publications (2)

Family

ID=29406709

Family Applications (1)

Country Status (10)

Cited By (1)

Families Citing this family (14)

Family Cites Families (9)

• 2003
  • 2003-02-21 US US10/369,396 patent/US6902662B2/en not_active Expired - Lifetime
  • 2003-04-28 MX MXPA04010708A patent/MXPA04010708A/es active IP Right Grant
  • 2003-04-28 CA CA002483568A patent/CA2483568A1/en not_active Abandoned
  • 2003-04-28 WO PCT/US2003/013361 patent/WO2003093399A1/en not_active Ceased
  • 2003-04-28 AT AT03728605T patent/ATE310064T1/de not_active IP Right Cessation
  • 2003-04-28 JP JP2004501536A patent/JP2005523988A/ja active Pending
  • 2003-04-28 RU RU2004134593/04A patent/RU2316576C2/ru not_active IP Right Cessation
  • 2003-04-28 EP EP03728605A patent/EP1501912B1/de not_active Expired - Lifetime
  • 2003-04-28 AU AU2003234293A patent/AU2003234293A1/en not_active Abandoned
  • 2003-04-28 DE DE60302352T patent/DE60302352T2/de not_active Expired - Fee Related

Non-Patent Citations (1)

Also Published As

Similar Documents

Legal Events